Electrical connectors which are designed for high current applications are made in a variety of configurations so that a male plug is mateable with a female receptacle. Most often, such connectors are made in a circular configuration, and one connector includes a coupling ring for mating the one connector with the mateable connector. The coupling ring may be of a screw-thread type or have a bayonet coupling configuration.
Various desired features and various problems are encountered in designing electrical connectors of the character described.
For instance, with high current applications, it is desirable to provide a visual indicating means which indicates to a user that the connector is fully mated with its complementary connector. For instance, U.S. Pat. Nos. 4,443,052; 4,497,530 and 4,534,607 are representative of the prior art and all show one form or another of a visual indicating means for the purpose described above. The visual indicating means of the prior art as represented by these patents have distinct disadvantages. For instance, the indicating means are difficult to see from a distance. Of equal or more significance is that the visual indicating means is not omnidirectional in that an operator must be looking at the connector from a specific vantage point in order to see the visual indicating means. This is disadvantageous particularly with circular connectors which could be mated in different angular orientations.
Another problem with connectors of the character described is in protecting the termination interface between the interior terminals and the conductors from the electrical cable. Such connectors are exposed to relatively large forces during mating, unmating and handling in comparison to smaller electronic-type connectors. Compounding this problem is the fact that many such connectors include a housing portion and/or a flexible boot extending rearwardly from the termination interface and which can be bent or disformed. This invention is directed to solving this problem by a very simple means of elongating the coupling ring to extend rearwardly beyond this interface.
Still another problem with electrical connectors of the character described is in providing an appropriate strain relief means for the electrical cable itself. Again, keeping in mind the "heavy" use of such connectors, either the strain relief means is too flexible for affording adequate protection for the cable or it is too rigid to afford an acceptable range of bending of the cable. This invention is directed to solving this problem by providing a strain relief means or boot which is provided with means for progressively varying the bending capabilities of the boot rearwardly of the connector.